Lenze E82xVxxxKxxxxx - Manual (Page 269)

Function library
Optimising the operating behaviour
Slip compensation
10
l
269 EDS82EV903 EN 3.0
Manual adjustment
Manual adjustment of the slip compensation is only required if the motor parameter
identification is not carried out. For this purpose, a first coarse adjustment of the slip
compensation can be carried out on the basis of the motor data. Fine adjustment will be
carried out empirically when the drive is running:
Coarse adjustment
1. Roughly determine the slip compensation on the basis of the motor data and enter
it into C0021:
s +
n
rsyn
* n
r
n
rsyn
@ 100 %
n
rsyn
+ f r
@ 60
p
s Slip constant (C0021) [%]
n
rsyn
Synchronous motor speed [min −1 ]
n
r
Rated motor speed according to motor nameplate [min −1 ]
f
r
Rated motor frequency according to motor nameplate
[Hz]
p Number of motor pole pairs (1, 2, 3, ...)
s + 1500 min
*1 *1435 min *1
1500 min *1
@ 100 % + 4.33 %
n
rsyn
+ 50Hz @ 60
2
+ 1500 min *1 Example of a 4−pole motor / 1435 rpm / 50 Hz:
Preset C0021 = 4.3 %
Fine adjustment
2. Correct C0021 with the drive running until load−dependent speed drops do not occur
anymore in the desired speed range between idling and maximum motor load. The
following holds true as a guide value for correct slip compensation:
– Deviation from the rated speed
£ 0.5 % for output frequency 5 ... 50 Hz (87 Hz)
– Higher deviations are possible during field weakening operation
)
Note!
If C0021 is set too high, the drive may get unstable.
Setting tips
ƒ With speed control, set C0021 = 0.0 with the internal process controller.
ƒ A negative slip (C0021 < 0) in the "V/f characteristic control" operating mode results
in a "smoother" drive behaviour in case of high load impulses or applications
including multiple motors.